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61.
Alessandra Pazini Luis Maqueira Harold C. Avila Felipe M. Valente Rian E. Aderne Davi Back Ricardo Q. Aucélio Marco Cremona Jones Limberger 《Tetrahedron letters》2018,59(31):2994-2999
The synthesis of a phenoxy-benzothiadiazole (BTD) derivative is reported for the first time. This derivative was employed as an intermediate in the obtention of two novel highly fluorescent aryl-phenoxy-BTD dyes. Their photophysical properties were evaluated in solution and the results indicate a strong intramolecular charge transfer (ICT) character in the excited state. The luminophore 3a, possessing a donor-BTD-phenoxide architecture, exhibits superior fluorescence quantum yield (0.67) than the designed acceptor-BTD-phenoxide dye (0.06). After electrochemical and photoluminescence characterization of thin films of 3a, an OLED with the configuration ITO/PEDOT:PSS/3a/TPBi/LiF/Al was constructed. This device displayed a green emission centered at 547?nm, with CIE coordinates of (0.40, 0.55). For comparison, an OLED using a previously reported luminescent BTD-pyridyl derivative was also constructed. The OLED made with the phenoxy-BTD derivative operated using less current density and led to higher irradiance and electrical stability, indicating the high potential of ArO-BTD dyes for future application in electroluminescent devices. 相似文献
62.
63.
Structured emission spectra have been observed from ND3 excited at 2139 Å and 2144 Å. The emission is short-lived (τ < 10?10 s) and has been assigned to the ND3() → ND3() fluorescence transition. 相似文献
64.
The conjugate additions of (2-piperidyl)acetate esters to acetylenic sulfones, followed by LDA-promoted intramolecular acylations, afforded cyclic enaminones that were readily converted into the corresponding 4-substituted 2-keto- or 2-hydroxyquinolizidines by stereoselective reduction and desulfonylation. This procedure was applied to the total synthesis of (-)-lasubine II from methyl (S)-(2-piperidyl)acetate and 2-(3,4-dimethoxyphenyl)-1-(p-toluenesulfonyl)ethyne. Similarly, methyl (+/-)-(2-piperidyl)acetate and 1-(p-toluenesulfonyl)propyne provided (+/-)-myrtine. 相似文献
65.
66.
David N. Harpp Thomas G. Back 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2-3):159-167
Abstract The low resolution mass spectra of alkyl and aryl sulfinamides containing alkyl, cycloalkyl, aryl and cyclic amine functions were recorded and the major fragmentation modes were elucidated with the aid of metastable peaks. In addition, the behavior of a variety of sulfinate esters upon electron-impact was similarly established. 相似文献
67.
Thomas G. Back Ziad Moussa Masood Parvez 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2004,116(10):1288-1290
68.
Liniquer Andr Fontana Josili Demetrio Siqueira Joice Ceolin Bernardo Almeida Iglesias Paulo Cesar Piquini Ademir Neves Davi Fernando Back 《应用有机金属化学》2019,33(7)
New mixed‐valence cobalt complexes with ligands derived from pyridoxal were synthesized and characterized, and their application as mimetics of the peroxidase enzyme was investigated. Single‐crystal X‐ray diffraction was used to analyze all complex structures in the solid state and their electrochemical behavior was investigated. A reactivity pattern was observed in the complex synthesis regarding the cobalt compounds from which analogous zwitterionic derivatives were obtained. The importance of these compounds lies in understanding their behavior in an oxidizing environment and evaluating whether they can activate hydrogen peroxide to oxidize phenolic compounds. In nature, enzymes called peroxidases, which efficiently oxidize phenolic compounds, trigger many reactions involving the activation of hydrogen peroxide to oxidize organic substrates. However, these enzymes present several disadvantages, including denaturation and elevated costs. Therefore, these limitations can be overcome by expanding research into the study of synthetic catalysts for the oxidation of phenolic compounds using hydrogen peroxide, which is a highly relevant field of bioinorganic chemistry. 相似文献
69.
Kwan Wook Song Tae Ho Lee Eui Jin Ko Kyung Hun Back Doo Kyung Moon 《Journal of polymer science. Part A, Polymer chemistry》2014,52(7):1028-1036
A poly[benzodithiophene‐alt‐di‐2‐thienyl‐quinoxaline] series (PBDTDPQ‐EH, PBDTDPQ‐OD, and PBDTDPQ‐HDT) was synthesized via Stille coupling. Deep highest occupied molecular orbital (HOMO) levels were achieved by the introduction of 2‐decyl‐4‐hexyl‐thiophen‐yl (HDT) side chains. The introduction of the various side chains increased the molecular weight of the polymers, and the polymers dissolved well in common organic solvents at room temperature. The HOMO energy level (?5.20 to ?5.49 eV) decreased because of the 2D conjugated structure. X‐ray diffraction analysis showed that PBDTDPQ‐OD had a slightly edge‐on structure. In the case of PBDTDPQ‐HDT, however, the structure was amorphous due to the thiophene side chain, and the extent of π stacking increased. After fabricating bulk‐heterojunction‐type polymer solar cells, the OPV characteristics were evaluated. The values of open‐circuit voltage (Voc), short‐circuit current (Jsc), fill factor, and power conversion efficiency (PCE) were 0.88 V, 7.9 mA cm?2, 45.4%, and 3.2%, respectively. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1028–1036 相似文献
70.
Weston MH Nakajima K Parvez M Back TG 《Chemical communications (Cambridge, England)》2006,(37):3903-3905
A novel ring-expansion protocol is based on the conjugate additions of cyclic alpha-vinylamines to (p-toluenesulfonyl)ethyne, followed by aza-Cope rearrangements of the resulting zwitterions, to afford medium and large-ring cyclic amines under remarkably mild conditions. 相似文献